Made a quart of black tea (in this case, an organic russian blend with pine smoke flavor), added about a quarter cup of demerara sugar, let it cool. To this, I added a splash of High Mountain kombucha (which is unpasteurized). Put a paper towel over neck, and placed just the ring from the mason jar over it (no lid). Put in cabinet, wait a week.
A week later, a symbiotic colony of bacteria and yeast (a scoby) has formed on the surface. It has turned much of the sugar and some of the other tea constituents into a drink that tastes like smoky, vinegary, hard apple cider. Alcohol content is probably low, maybe 1-2%. It is slightly effervescent. It looks like a big blubbery white disk of calimari-like texture.
You can see from the cloudiness that there is still plenty of yeast at play here. There's some residual sweetness, too. I'm going to put the scoby into a fresh quart of sweet tea and seal the jar up completely (with the lid), place in ziplock bag in the fridge (to contain any shatterage or leakery) and see if I can "lager" it for a couple of days to carbonate it and clean up the flavor.
Now, the crunchy types say that kombucha "de-toxifies" and cures everything, but I don't buy it. I just like growing different kinds of bacteria and fungus. I'm also making my own "kefir", but it's no where near as interesting. Milk + kefir = more kefir. Kefir is in quotes because it's just a storebought cultured buttermilk with slightly different bacteria, no neato kefir grains.